Container assembly and method for making assembly

ABSTRACT

The present invention is directed to a method of assembling a container including an inner tube contained within an outer tube. The method includes providing an outer tube, providing a spacing element adjacent the open top of the outer tube and inserting an inner tube within the outer tube. The spacing element provides for venting of air from between the inner and outer tubes through the top of the container during assembly thereof.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional PatentApplication No. 60/444,404, filed Feb. 3, 2003, which is herebyincorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a container assembly and methodof manufacture thereof. More particularly, the present invention isdirected to a method of assembling a container having an inner tubecontained within an outer tube.

[0004] 2. Description of Related Art

[0005] Glass collection containers have historically been used forcollection of body fluids such as blood and urine. For example, glassinherently provides excellent vacuum retention for evacuated tubes, aswell as excellent moisture retention for collection tubes containingliquid additives.

[0006] However, the medical industry has been transitioning from glassto plastic for a variety of reasons including the increased safety of aplastic tube, which tolerates impact stresses without breaking.Unfortunately, no single plastic material that is commerciallyacceptable from a cost and performance perspective exhibits thebeneficial properties of glass. For example, plastic tubes tend toexhibit either good vacuum retention or good moisture retention, but nosingle plastic material exhibits both properties to a degree useful forevacuated collection tubes.

[0007] Various solutions to this problem have been devised. Theseinclude, for example, the tube-in-tube configurations described in U.S.Pat. Nos. 6,354,452 and 5,871,700, and U.S. patent application Ser. Nos.09/933,653 and 10/114,542, the disclosures of which are herebyincorporated by reference. Such tube-in-tube configurations typicallyinvolve an inner tube positioned within an outer tube to form acontainer, with each of the tubes providing distinct properties to thecontainer. More particularly, one of the tubes may provide a water vaporbarrier to the container, while the other tube may provide a gas barrierto the container, thereby effectively forming a container which has bothgas barrier and water vapor barrier properties.

[0008] For example, U.S. Pat. No. 6,354,452 describes a containerassembly that includes an inner tube formed from a plastic that issubstantially inert to bodily fluids and an outer tube that is formedfrom a different plastic. Collectively, the container assembly is usefulfor providing an effective barrier against gas and water permeability inthe assembly and for extending the shelf-life of the container assembly,especially when used for blood collection. However, such a close nestingarrangement of the containers may create difficulties in the assemblyprocess. For example, insertion of one container into another containercan create some inherent manufacturing difficulties, such as the forcecreated and exerted by trapped air upon insertion of the inner containerinto the outer container. Other difficulties may include the techniquesby which the tubes can be held together securely and avoidance ofleakage from the inner tube into the space between the two tubes.

[0009] Accordingly, a need exists for a method of assembling a containerincluding an inner tube contained within an outer tube that eliminatesthe presence of a pressure gradient exerted by trapped air during theinsertion of an inner container into an outer container.

SUMMARY OF THE INVENTION

[0010] The present invention provides a method of assembling a containerincluding inserting an inner tube within an outer tube, with the use ofa spacing element for venting of air between the two tubes toatmospheric pressure during insertion of the inner tube within the outertube. The outer tube includes a closed bottom, an open top and a sidewall extending therebetween, defining an inner surface and an outersurface. The inner tube also includes a closed bottom, an open top and aside wall having an inner and outer surface extending therebetween. Aspacing element is provided adjacent the open top of the outer tube. Thespacing element includes a central opening extending therethrough and atleast one extending member extending within the open top of the outertube. In the method of assembly, the inner tube is inserted within theouter tube, such that the spacing element extends between the innersurface of the outer tube and the outer surface of the inner tube. Assuch, any air between the two tubes is vented to atmospheric pressureduring insertion of the inner tube within the outer tube.

[0011] More particularly, the inner tube may be inserted through thecentral opening of the spacing element, with the extending member of thespacing element trapped between the outer tube and the inner tube. Whenthe inner tube is advanced within the outer tube, the extending membercauses the wall of either the inner tube or the outer tube to at leastpartially deform to permit any air trapped between the two tubes toescape to atmospheric pressure. Accordingly, any pressure build-upbetween the two tubes can be effectively eliminated. Desirably, theinner tube is constructed of a material that is softer than the outertube and the extending member of the spacing element is constructed of amaterial that is at least as hard as a material forming the outer tube,such that the softer inner tube will deform during insertion within theouter tube, based on the interference from the extending member betweenthe outer tube and the inner tube.

[0012] Desirably, at least a portion of the inner tube has an externaldiameter which is smaller than an internal diameter of the outer tube toform an annular gap therebetween. Also, the side wall of the inner tubeis preferably shorter than the side wall of the outer tube, and ispreferably flared outwardly adjacent the open top of the inner tube forsealing and supporting engagement with the side wall of the outer tube.

[0013] The spacing element may further include a rim associated with theopen top of the outer tube. In particularly desirable embodiments, thespacing element may include at least two extending members equallyspaced on opposing sides of the spacing element, and may be airpermeable.

[0014] The present invention is also directed to a container assemblyincluding an inner tube disposed within an outer tube with an annulargap therebetween. The annular gap extends between the inner surface ofthe outer tube and the outer surface of the inner tube, and is inequilibrium with atmospheric pressure at least at the time of assembly.In particular, the annular gap is vented to atmospheric pressure duringassembly of the container, such as by imparting an interferenceengagement between the inner tube and the outer tube adjacent the opentop of the outer tube, desirably by providing a spacing elementtherebetween during assembly.

[0015] The side wall of the inner tube is shorter than the side wall ofthe outer tube, and may be flared outwardly adjacent the open top of theinner tube for sealing and supporting engagement with the side wall ofthe outer tube.

[0016] In a further embodiment, the present invention is directed to aspacer element for venting air between an inner tubular member insertedwithin an outer tubular member. The element includes a rim portionforming a central opening therethrough and adapted for placement at anopen top of the outer tubular member. The spacer element furtherincludes at least one depending portion which is adapted to extendbetween the inner tubular member and the outer tubular member duringinsertion of the inner tubular member through the central opening. Thedepending portion may be adapted for outward flexing upon force, anddesirably includes at least two depending portions equally spaced aboutthe rim. The spacer element is desirably in the form of a unitaryring-like structure having a bottom surface for resting on the open topof the outer tubular element, and a plurality of depending portionsequally spaced about the rim.

[0017] In yet a further embodiment, the present invention is directed toa method of assembling a container including an inner tube containedwithin an outer tube, and maintaining the inner tube within the outertube. The outer tube includes a side wall having an inner surface with arecess, such as a circumferential groove, adjacent an open top thereof.The side wall of the inner tube is shorter than the side wall of theouter tube, and includes an outwardly flared portion adjacent the opentop of the inner tube. During assembly, the inner tube is insertedwithin the open top of the outer tube to a position in which theoutwardly flared portion of the inner tube extends below a top edge ofthe recess of the outer tube, thereby causing air trapped between theinner tube and the outer tube to pass through the recess and vent toatmospheric pressure. Preferably, the outwardly flared portion of theinner tube deforms below the top edge of the recess of the inner surfaceof the outer tube to cause air trapped between the inner tube and theouter tube to pass through the recess. The outwardly flared portion ofthe inner tube may then contact the top edge of the recess, therebysealingly supporting the inner tube within the outer tube. Desirably,the inner tube is biased against the top edge of the recess, such asthrough pressure contact between the bottom surfaces of the tubes. Inone particular embodiment, the inner surface of the inner tube mayfurther include a protrusion adjacent the recess, for causing theoutwardly flared portion of the inner tube to deform when the outwardlyflared portion of the inner tube extends below the top edge of therecess of the inner surface of the outer tube.

[0018] In another embodiment of the present invention, a containerassembly including an inner tube maintained within an outer tube isprovided, in which the inner surface of the side wall of the outer tubeincludes a recess adjacent the open top thereof. The side wall of theinner tube includes an outwardly flared portion adjacent the open top ofthe inner tube and extends within the recess of the outer tube. The topof the outward flared portion of the inner tube is biased against a topedge of the recess of the outer tube to sealingly support the inner tubewithin the outer tube.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1A is a side elevational view of a container assembly of theprior art;

[0020]FIG. 1B is a cross-sectional view taken along line B-B of theprior art container assembly of FIG. 1A;

[0021]FIG. 1C is an exploded perspective view of the prior art containerassembly of FIG. 1A;

[0022]FIG. 2 is an exploded perspective view of one embodiment of thepresent invention depicting an outer tube, a spacing element, and aninner tube during assembly;

[0023]FIG. 3 is a perspective view of the spacing element of FIG. 2 inaccordance with the present invention;

[0024]FIG. 4A is a cross-sectional view of the inner tube partiallyinserted in the outer tube during assembly;

[0025]FIG. 4B is a cross-sectional view of the inner tube fully insertedin the outer tube during assembly;

[0026]FIG. 4C is a cross-sectional view of a container fully assembledin accordance with the method of the present invention;

[0027]FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 4A,showing assembly in accordance with one embodiment of the presentinvention;

[0028]FIG. 6 is a cross-sectional view of a container during assembly inaccordance with another embodiment of the present invention;

[0029]FIG. 7 is a perspective cross-sectional view of an outer tubehaving a recessed groove in accordance with a further embodiment of thepresent invention;

[0030]FIG. 8A is a cross-sectional view of an inner tube partiallyinserted in the outer tube of FIG. 7 during assembly;

[0031]FIG. 8B is a cross-sectional view of a container assembly havingthe side wall of an inner tube below the recess in the outer tube ofFIG. 7 during assembly;

[0032]FIG. 8C is a cross-sectional view indicating the air path when theside wall of the inner tube is below the recess of the outer tube ofFIG. 7;

[0033]FIG. 8D is a cross-sectional view of the inner tube after assemblywith the side wall of the inner tube in contact with a top edge of therecess;

[0034]FIG. 9A is a perspective cross-sectional view of an outer tubehaving protrusions and a recess in accordance with a further embodimentof the present invention;

[0035]FIG. 9B is a cross-sectional view of the outer tube of FIG. 9A;and

[0036]FIG. 10 is a cross-sectional view of a container assembly having aclosure in accordance with another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0037] While this invention is satisfied by embodiments in manydifferent forms, there is shown in the drawings and will herein bedescribed in detail, the preferred embodiments of the invention, withthe understanding that the present disclosure is to be considered asexemplary of the principles of the invention and is not intended tolimit the invention to the embodiments illustrated. Various othermodifications will be apparent to and readily made by those skilled inthe art without departing from the invention. The scope of the inventionwill be measured by the appended claims and their equivalents.

[0038]FIGS. 1A, 1B, and 1C are directed to a container assembly 100 ofthe prior art. The assembly 100 includes an outer tube 112, an innertube 114 and a closure 116. Outer tube 112 is unitarily formed andincludes a generally spherical closed bottom wall 118, an open top 120and a cylindrical side wall 122 extending therebetween, whereby sidewall 122 slightly tapers from open top 120 to closed bottom wall 118.Inner tube 114 is unitarily formed and includes a generally sphericalclosed bottom wall 126, an open top 128, and a cylindrical side wall 130extending therebetween, whereby side wall 130 slightly tapers from opentop 128 to closed wall 126. Side wall 130 includes an outwardly flaredouter surface 136 adjacent open top 128 of inner tube 114. Asubstantially cylindrical space 154 is defined between inner tube 114and outer tube 112. Assembly 100 is assembled by slidably insertinginner tube 114 into open top 120 of outer tube 112. During suchassembly, pressure may build up in the space 154 between the inner tube114 and the outer tube 112. Such pressure can make assembly difficult,and can result in the inner tube 114 not being fully inserted within theouter tube 112, or being gradually forced out of the outer tube 112 overtime.

[0039] The present invention is directed to a method of assembling acontainer having an inner tube contained within an outer tube whichovercomes these problems. FIG. 2 illustrates a configuration utilized toassemble a container assembly 10 according to a method of the presentinvention. The configuration includes an outer tube 12, an inner tube14, and a spacing element 16.

[0040] Outer tube 12 is unitarily formed from a first plastic materialand is similar in construction to the prior art outer tube 12 describedabove, including a generally spherical closed bottom wall 18, an opentop 20 and a cylindrical wall 22 extending therebetween. Side wall 22may slightly taper from open top 20 to closed bottom wall 18. Outer tube12 defines a length “a” from the interior of the bottom wall 18 to theopen top 20. Side wall 22 of outer tube 12 includes a generallycylindrical inner surface 24 with an inside diameter “b” and an outersurface 25.

[0041] Inner tube 14 is unitarily formed from a second plastic materialand is similar in construction to the prior art inner tube 14 describedabove, including a generally spherical closed bottom wall 26, an opentop 28 and a cylindrical side wall 30 extending therebetween. Side wall30 may slightly taper from open top 28 to closed bottom wall 26. Innertube 14 defines an external length “c” that is desirably less thaninternal length “a” of outer tube 12. Side wall 30 of inner tube 14includes a generally cylindrical section 32 extending from bottom wall26 toward open top 28 of inner tube 14, and includes an inner surface 39and an outer surface 41.

[0042] As illustrated in FIG. 4A, side wall 30 is further characterizedby a circumferentially enlarged section 34 adjacent open top 28 formingan outwardly flared outer surface 36 adjacent cylindrical portion 32 ofside wall 30 and a cylindrical outer surface 38 adjacent open top 28 ofinner tube 14. Additionally, enlarged top section 34 of side wall 30includes a conically flared inner surface 40 adjacent open top 28.

[0043] Cylindrical portion 32 of side wall 30 of inner tube 14, definingthe inner surface 39 of the inner tube 14, desirably has a diameter “d”that is less than inside diameter “b” of side wall 22 on outer tube 12.In this manner, an annular gap 60 is established between the outer tube12 and the inner tube 14.

[0044] As noted, the outer tube 12 and the inner tube 14 are formed fromplastic materials, and are desirably distinct plastic materialsexhibiting different properties. Neither plastic material is required tomeet all of the sealing requirements for the container. However, therespective plastic materials cooperate to ensure that the assemblyachieves the necessary sealing, adequate shelf life and acceptableclinical performance. Preferably, one of the tubes may be formed from amaterial that exhibits acceptable gas vapor barrier characteristics, andthe other of the containers may be formed from a material that providesa moisture barrier. The inner tube should also be formed from a materialthat has a proper clinical surface for the material being stored in thecontainer assembly. Examples of particularly useful materials includepolymeric materials such as polyethylene terephthalate, polypropylene,polystyrene, polycarbonate, and the like. In one preferred embodiment,outer tube 12 is formed from a polyethylene terephthalate, and innertube 12 is formed from polypropylene. Such an embodiment providesexcellent gas and vapor barrier properties, and provides the inner tube12 as a softer material than the outer tube 12, as will be discussed inmore detail herein.

[0045]FIG. 3 illustrates the spacer or spacing element 16 of the presentinvention. The spacing element 16 functions to allow air to vent out ofthe container assembly 10 during assembly, such as by deforming one orboth of the inner tube 14 or the outer tube 12 to form a gap.Additionally, the spacing element 16 functions to improve alignment ofthe inner tube 14 within the outer tube 12 during assembly. The spacingelement 16 includes a central opening 50 and at least one extendingmember 52. The spacing element is preferably a unitary structureincluding a circumferential rim 54 defining the central opening 50therethrough. The central opening 50 has a diameter “f” which issubstantially equivalent to the outer diameter of the inner tube 14. Therim 54 of the spacing element 16 preferably rests on the open top 20 ofthe outer tube 12, thereby aligning the central opening 50 with the opentop 20 of the outer tube 12. During assembly, inner tube 14 is insertedinto the outer tube 12 through the central opening 50.

[0046] The spacing element 16 further includes at least one extendingmember 52 having an inner surface 56 and an outer surface 58. Desirably,the spacing element 16 includes a plurality of extending members 52equally spaced along the rim 54 on opposing sides of the spacing element16. The extending members 16 may be of any size and geometric shape,such as cylindrically-shaped, rod-shaped, or the like, so long as theyare capable of establishing a mechanism for air trapped between outertube 12 and inner tube 14 to vent to atmospheric pressure duringinsertion of inner tube 14 within outer tube 12, as will be discussed inmore detail. It is contemplated that spacing element 16 may be providedin a variety of forms, so long as it provides structure for interferenceengagement during insertion of the inner tube 14 within the outer tube12 to vent any air trapped therebetween to atmospheric pressure. Forexample, spacing element 16 may be provided as a flexible rigidstring-like material, or may be provided as a plurality of rod-likestructures tied together through a string to form the structure.

[0047] The spacing element 16 may be made of any rigid flexiblematerial, and is desirably a unitary structure constructed of plasticmaterial. Preferably, the material forming the spacing element 16, or atleast the extending members 52 of the spacing element 16, be at least ashard as the material forming either the outer tube 12 or the inner tuber14, or both. Alternatively, the extending members 52 of the spacingelement 16 may be hollow or formed of an air preamble material toprovide for venting.

[0048] As indicated, the spacing element 16 provides a mechanism forventing any air trapped between the outer tube 12 and the inner tube 14to atmospheric pressure during insertion of the inner tube 14 within theouter tube 12 by providing an interference engagement therebetween.During assembly, the spacing element 16, and in particular the extendingmembers 52, are positioned or located between the inner surface 24 ofthe outer tube 12 and the outer surface 41 of the inner tube 14. Uponinsertion of the inner tube 14 into the outer tube 12, the extendingmembers 52 create an interference engagement between the inner tube 14and the outer tube 12 at the point of contact therebetween, whichprovides for deformation of either the inner tube 14 or the outer tube12, thereby creating a uniform venting gap 61 to allow venting of airduring assembly.

[0049]FIGS. 4A-4C will be described in connection with assembly of thecontainer in accordance with the present invention. FIG. 4A illustratesa cross-section of the container 10 during assembly. Assembly of thecontainer 10 typically occurs by a press-fit technique, whereby theinner tube 14 is press-fit into the outer tube 12 along an assemblyline, such as through the use of a press mechanism, air pressure, orother means for press-fitting an inner tube within an outer tube. Priorto inserting inner tube 14 within outer tube 12, the spacing element 16is in contact with the open end 20 of the outer tube 12, such that theouter surface 58 of the extending members 52 is in contact with theinner surface 24 of the outer tube 12. As shown in FIG. 4A, duringassembly, the inner tube 14 is inserted into the outer tube 12 throughthe central opening 50 of the spacing element 16. As the inner tube 14is inserted through the central opening 50 of the spacing element 16,the outer surface of the inner tube 14 makes contact with the innersurface 56 of the extending members 52. This contact may cause extendingmembers 52 to flex outwardly against the inner surface 24 of outer tube12.

[0050] Even in embodiments in which there is an annular gap 60 formedbetween the two tubes, the outer diameter of the inner tube 14 issubstantially similar to the inner diameter of the outer tube 12.Accordingly, as the inner tube 14 is inserted into the outer tube 12,the spacing element 16 creates an interference engagement between thetwo tubes. The geometry and material structure of the spacing elementand the two tubes causes deformation to occur based on this interferenceengagement. For example, in embodiments where the inner tube is softerthan the outer tube and the spacing element 16 is constructed of amaterial which is at least as hard as the outer tube, the interferenceengagement will cause the side wall 22 of the inner tube 14 to deform inshape, as shown in FIG. 5. This creates a vent gap 61, which will permitventing of air from between the two tubes out through the top of theassembly adjacent the contact point of the two tubes to atmosphericpressure, thereby eliminating any build up of pressure.

[0051] As the inner tube 14 continues to be inserted within the outertube 12 as illustrated in FIG. 4B, at least a portion of the outersurface 41 of the inner tube 14 may come into contact with at least aportion of the inner surface 24 of the outer tube 12, such as thecontact between the respective bottom surfaces 18 and 26. Additionally,at least a portion of the enlarged section 34 of the inner tube 14adjacent the open top 28 of the inner tube 14 frictionally engages withthe inner surface 56 of the extending members 52 of the spacing element16. Upon contact of the extending members 52 of the spacing element 16with the enlarged section 34 of the inner tube 14, the enlarged section34 of the inner tube 14 deforms further allowing venting of trapped airwithin the outer tube 12 to travel through the annular gap 60 towardsthe open top of the inner tube 14. Upon completion of the containerassembly 10, the spacing element 16 is removed, thereby allowingcylindrical outer surface 38 of the inner tube 14 to sealingly andsupportingly engage with the inner surface 24 of the outer tube 12, asshown in FIG. 4C.

[0052] A container closure can further be provided on the open end ofthe container, such as an elastomeric stopper as in known in the art.Moreover, the container can be evacuated using any evacuationtechniques. The container assembled as such is particularly useful as anevacuated blood collection container for blood collection procedures, asare commonly known in the art.

[0053]FIG. 6 illustrates a cross-sectional view of the container duringassembly in a variation. In particular, FIG. 6 illustrates analternative arrangement where the extending member 52 of the spacingelement 16 is at least as hard as the inner tube 14, with the outer tube12 made of a softer material. This arrangement causes the outer tube 12to deform at the areas in contact with the outer surface 58 of theextending members 52, thereby creating an elliptical-like shape to formthe venting gap 61.

[0054] While the above-described specific embodiments of the presentinvention, other variations are contemplated. For example, the extendingmembers 52 of the spacing element 16 may extend along the entire lengthof the container assembly during assembly to achieve greater venting.Additionally, while the method of assembling the container assembly 10was described with the spacing element 16 associated with the open top20 of the outer tube 12, the container assembly 10 alternatively may beassembled by having the spacing element 16 associated in frictionalengagement with the outer surface 41 of the inner tube 14 prior toassembly. Therefore, the spacing element 16 comes into contact and restson the open top 20 of outer tube 12 when inserting the inner tube 14into the outer tube 12. It is also contemplated that, in automatedassembly procedures involving a press mechanism for insertion of theinner tube 14 within the outer tube 12, the spacing element 16 can beautomatically removed by frictional engagement with the press mechanismas it exits the inner tube 14.

[0055]FIGS. 7-8D depict a further embodiment of the invention, whichincludes many components which are substantially identical to thecomponents of FIGS. 2-6. Accordingly, similar components performingsimilar functions will be numbered identically to those components ofFIGS. 2-6, except that a suffix “a” will be used to identify thosesimilar components in the embodiments of FIGS. 7-8D, a suffix “b” willbe used to identify those similar components in FIGS. 9A and 9B, and asuffix “c” will be used to identify those similar components in FIG. 10.

[0056] In the embodiment of FIGS. 7-8D, the outer tube 12 a includes abottom wall 18 a, an open top 20 a, and a side wall 22 a extendingtherebetween. The side wall 22 a defines an inner surface 24 a and anouter surface 25 a. The inner surface 24 a further includes a recessedarea, such as groove or recess 70 adjacent the open top 20 a of theouter tube 12 a. While FIG. 7 illustrates the outer tube 12 a having therecess 70 extending circumferentially around the inner surface 24 a ofthe outer tube 12 a, it is contemplated that the recess 70 of the outertube 12 a may take other forms. For example, it may extendlongitudinally to the open end 20 a of the outer tube 12 a.Additionally, the outer tube 12 a may further include a longitudinalgroove (not shown) extending between the recess 70 on the inner surface24 a of the outer tube 12 a to the open end 20 a of the outer tube 12 a.Alternatively, the recess may encompass the interior surface of theouter tube and/or the exterior surface of the inner tube having anirregular surface texture, such as a roughened surface. In such anembodiment, such surface texture may provide a path for fluid flow outto the external environment, and/or may provide a mechanism forretaining the inner tube within the outer tube in a frictionalengagement. Other variations as understood by one skilled in the art mayalso be utilized.

[0057] The inner tube 14 a includes the closed bottom 26 a, an open top28 a, and a side wall 30 a having an inner surface 24 a and an outersurface 25 a extending therebetween. The side wall 30 a of the innertube 14 a is shorter than the side wall 22 a of the outer tube 12 a. Theside wall 30 a of the inner tube 14 a also includes the outwardly flaredportion 36 a adjacent the open top 28 a of the inner tube 12 a.

[0058]FIGS. 8A, 8B, 8C and 8D further illustrate a method according tothis embodiment of the present invention. During assembly, asillustrated in FIG. 8A, the inner tube 14 a is provided within the outertube 12 a. The relative diameters of the outer tube 12 a and the innertube 14 a establish a hoop stress on the outwardly flared portion 36 a,thereby causing the outwardly flared portion 36 a to become radiallycompressed. As shown in FIG. 8B, the inner tube 14 a is inserted withinthe open top 20 a of the outer tube 12 a to a position in which theoutwardly flared portion 36 a of the inner tube 14 a is forced to extendbelow a top edge 72 of the recess 70 of the inner surface 24 a of theouter tube 12 a. At this point, the nature of the construction of innertube 14 a with outwardly flared portion 36 a will cause the outwardlyflared portion 36 a to relax or return to a normal uncompressed state,such that any hoop stress will be relieved and outwardly flared portion36 a will radially expand within recess 70. As the inner tube 14 a isinserted to a position in which the respective bottoms of the tubecontact, further insertion force against the inner tube will cause theinner tube 14 a to be biased, and will cause the side wall 22 a of theinner tube to bend and/or deform with continued pressure exerted on theinserted inner tube 14 a.

[0059] To complete assembly of container assembly 10 a, the insertionpressure exerted against inner tube 14 a is released. The bias exertedbetween the bottom surfaces of the two tubes causes the inner tube 14 ato be forced toward the open end of the outer tube 12 a. The outwardlyflared surface 36 a is then trapped within recess 70, and a portion ofthe outwardly flared surface 36 a, such as the top edge of the innertube 14 a, is forced in abutting relation against the top edge 72 ofrecess 70. This abutting interference relationship prevents inner tube14 a from being removed or forced out of containment within outer tube12 a. Alternatively, the outer wall portion of outwardly flared surface36 a may be forced radially outwardly against the sidewall surfacewithin recess 70 from the bias, thereby exerting an abuttinginterference force to maintain inner tube 14 a in place.

[0060] It is contemplated that the biasing force between the two tubescan be established, for example, through the build-up of air pressurebetween the two tubes, without the need for contact between the bottomsurfaces. As such, the insertion force must be sufficient to overcomethis build up of pressure to force the inner tube to a location at whichthe outwardly flared portion 36 a extends within the recess 70, and canthereafter be released, permitting the built-up pressure between the twotubes to bias the inner tube 14 a upwardly toward the open end of outertube 12 a, forcing abutting engagement against top edge 72 of recess 70.

[0061] Alternatively, any pressure build-up between the two tubes can bevented or released during assembly. For example, as illustrated by thearrows in FIG. 8C, the bias between the two tubes can deform the innertube 14 a. The bending and/or deformation moves the top end of the innertube 14 a adjacent outwardly flared surface 36 a out of contact with theinner surface of the outer tube 12 a, establishing a path for airtrapped between the two tubes to flow up towards the open top 20 a ofthe outer tube 12 a and escape through the recess 70 and vent toatmospheric pressure. As such, any air build up or trapped between thetwo tubes can vent through the air channel established by eliminatingthe contact between the inner tube and the inner surface of the outertube, and continue venting up through the recess and out to ambient air.The bias of the contact between the two tubes can then force the innertube 14 a toward the open end of the outer tube 12 a, with the outwardlyflared surface 36 a of the inner tube 14 a contacting the top edge 72 ofthe recess 70, thereby sealingly supporting the inner tube 14 a withinthe outer tube 12 a. At this point, any pressure gradient presentbetween the inner tube 14 a and the outer tube 12 a is equilibriated toatmospheric conditions.

[0062] Alternatively, the biasing mechanism could be a structuralelement of one of the inner tube 14 a or outer tube 12 a, or may be adistinct separate element. For example, the bottom of the outer tube 12a could have a convex feature that is able to move slightly downward inresponse to pressure from the inner tube 14 a, but remain biased in theupward direction. An arch-shaped member that would act similarly couldbe placed into the bottom of the outer tube 12 a prior to insertion ofthe inner tube 14 a. Or, a substantially immovable feature could beplaced or molded into the bottom of the outer tube 12 a, with the bottomof the inner tube 14 a made to deform slightly upon contact with theimmovable feature, but to bias upwards upon removal of the insertionforce. Further, as indicated above, it is contemplated that no biasingforce will be required if sufficient trapped air remains to force theinner tube 14 a up against the groove with sufficient force.

[0063] It is also possible to include only a vertical groove at only atop portion of the outer tube 12 a. Upon insertion of an inner tube 14 awith a flared out top region, the vertical groove will provide a pathfor air to escape from the annular gap region. The length of the grooveis designed such that at least a portion of the flared region 36 a ofthe inner tube 14 a will move past the bottom of the groove uponassembly, to thereby provide a 360° circumferential seal.

[0064] A variation on the embodiment of FIGS. 7-8D is illustrated inFIGS. 9A and 9B. FIG. 9A illustrates an outer tube 12 b having at leastone protrusion 80 adjacent the recess 70 b. Preferably the outer tube 12b includes a plurality of protrusions 80 equally spaced about thecircumference of the inner surface outer tube 12 b adjacent the recess70 b. The protrusions 80 extends radially inwardly, thereby contactingthe side wall 30 b of the inner tube 14 b as illustrated in FIG. 9B.Upon contact, the protrusions 80 cause at least a portion of the sidewall 30 b of the inner tube 14 b to deform outwardly, creating theannular 60 b in between protrusions 80. The protrusions 80 may be anyshape or size so long as it is made of a material harder than the innertube 14 b.

[0065]FIG. 10 illustrates another embodiment of the present invention.In this embodiment, it is possible to size the tubes 12 c, 14 c suchthat the annular gap 60 c exists between the outer tubes 12 c and theinner tubes 14 c over the entire length of the container assembly 10 c,as opposed to providing the inner tube 14 c with a press-fit region asdiscussed above. In this embodiment protrusions 80 are provided betweenthe tubes at one or more circumferentially and longitudinally spacedlocations, to center the inner tube 14 c within the outer tube 12 c. Theprotrusions 80 may be designed to slightly deform upon insertion of theinner tube 14 c, such that the inner tube 14 c and outer tube 12 c aresecurely assembled, and the inner tube 14 c cannot move or fall out. Theprotrusions 80 typically would not extend the entire length nor theentire circumference of the assembly.

[0066] The tubes are further secured, and spaced, by use of a uniqueclosure, the closure being of one or more components. The closure has aconventional stopper 84 that extends over and into the interior of theinner tube 14 c, and the closure further contains a ring 86 that extendsinto the annular gap 60 c. The ring 86 assists in securing the assembly,and also provides a seal against leakage of collected fluid into theannular gap 60 c between the tubes. The stopper 84 is typically of aconventional stopper material such as rubber. The ring 86 may be of thesame material as the stopper 84, but should be rigid and tough in natureto withstand forces applied during insertion of the ring 86 into theannular gap 60 c. The remainder of the closure, if two piece, is likelya rigid plastic that fits snugly over the stopper.

[0067] While the present invention has been described in terms ofspecific embodiments, it is further contemplated that the assembly andthe method of manufacturing thereof can be used with other applications.

The invention claimed is:
 1. A method of assembling a containercomprising an inner tube contained within an outer tube, the methodcomprising: providing an outer tube having a closed bottom, an open topand a side wall extending therebetween, said side wall defining an innersurface and an outer surface; providing a spacing element adjacent theopen top of the outer tube, said spacing element including a centralopening extending therethrough and at least one extending memberextending within the open top of the outer tube; and inserting an innertube within the outer tube through the central opening of the spacingelement, said inner tube having a closed bottom, an open top and a sidewall extending therebetween, said side wall defining an inner surfaceand an outer surface, at least a portion of said inner tube having anexternal diameter which is smaller than an internal diameter of theouter tube to form an annular gap therebetween; wherein at least asportion of the spacing element extends between the inner surface of theouter tube and the outer surface of the inner tube during assembly toallow for venting of air from the annular gap to atmospheric pressureduring insertion of the inner tube within the outer tube.
 2. The methodof claim 1, further comprising the step of removing the spacing elementafter venting of air from the annular gap.
 3. The method of claim 2,further comprising the step of providing a closure for the container. 4.The method of claim 3, further comprising the step of evacuating thecontainer.
 5. The method of claim 1, wherein the side wall of the innertube is shorter than the side wall of the outer tube.
 6. The method ofclaim 1, wherein said spacing element includes a rim associated with theopen top of the outer tube.
 7. The method of claim 1, wherein the sidewall of the inner tube is flared outwardly adjacent the open top of theinner tube for supporting engagement with the side wall of the outertube.
 8. The method of claim 7, wherein the flared side wall adjacentthe open top of the inner tube deforms about said spacing element toallow for venting of air from the annular gap to atmospheric pressure.9. The method of claim 7, wherein at least a portion of the outersurface of the inner tube is in contact with at least a portion of theinner surface of the outer tube and the at least one spacing member isin frictional engagement with at least a portion of the flared side wallof the inner tube adjacent the open top of the inner tube during ventingof air from the annular gap.
 10. The method of claim 9, wherein theouter surface of the closed bottom of the inner tube is in contact withthe inner surface of the closed bottom of the outer tube during ventingof air from the annular gap.
 11. The method of claim 1, wherein thespacing element includes at least two extending members equally spacedon opposing sides of said spacing element.
 12. The method of claim 1,wherein the at least one extending member of the spacing element is airpermeable.
 13. The method of claim 1, wherein the at least one extendingmember of the spacer element comprises a material that is at least ashard as a material forming the outer tube.
 14. A container assemblycomprising: an outer tube having a closed bottom, an open top and a sidewall extending therebetween, said side wall defining an inner surfaceand an outer surface; an inner tube disposed within the outer tube andhaving a closed bottom, an open top and a side wall extendingtherebetween, the side wall of the inner tube being shorter than theside wall of the outer tube and flared outwardly adjacent the open topof the inner tube for sealing and supporting engagement with the sidewall of the outer tube; and an annular gap extending between the innersurface of the outer tube and the outer surface of the inner tube inequilibrium with atmospheric pressure at the time of assembly, whereinthe annular gap is vented to atmospheric pressure during assembly of thecontainer by imparting an interference engagement between the inner tubeand the outer tube adjacent the open top of the outer tube.
 15. Thecontainer assembly of claim 14, wherein the outer container is formedfrom a polymeric material.
 16. The container assembly of claim 15,wherein the outer container comprises polyethylene terephthalate. 17.The container assembly of claim 14, wherein the inner tube is formedfrom a polymeric material.
 18. The container assembly of claim 17,wherein the inner tube comprises polypropylene.
 19. The containerassembly of claim 14, wherein the interference engagement between theinner tube and the outer tube is established through a spacing elementproviding at the open end of the outer tube during assembly.
 20. Thecontainer assembly of claim 19, wherein the spacing element includes atleast one extending member extending within the open top of the outertube during assembly.
 21. The container assembly of claim 20, whereinthe extending member of the spacing element comprises a material whichis at least as hard as a material forming the outer tube.
 22. A spacerelement for venting of air between an inner tubular member insertedwithin an outer tubular member, the spacer element comprising a rimportion forming a central opening therethrough and adapted for placementat an open top of the outer tubular member, and at least one dependingportion adapted to extend between the inner tubular member and the outertubular member during insertion of the inner tubular member through thecentral opening.
 23. The spacer element of claim 22, wherein the atleast one extending element is adapted for flexing outwardly upon force.24. The spacer element of claim 22, comprising at least two dependingportions equally spaced about said rim.
 25. The spacer element of claim22, comprising a unitary ring-like structure having a bottom surface forresting on the open top of the outer tubular element and including aplurality of depending portions equally spaced about said rim.
 26. Amethod of assembling a container comprising an inner tube containedwithin an outer tube, the method comprising: providing an outer tubehaving a closed bottom, an open top and a side wall extendingtherebetween, said side wall defining an inner surface and an outersurface, said inner surface having a recess adjacent the open topthereof; providing an inner tube within the outer tube, said inner tubehaving a closed bottom, an open top and a side wall having an innersurface and an outer surface extending therebetween, the side wall ofthe inner tube being shorter than the side wall of the outer tube andincluding an outwardly flared portion adjacent the open top of the innertube; inserting the inner tube within the open top of the outer tube toa position in which the outwardly flared portion of the inner tubeextends below a top edge of the recess of the inner surface of the outertube; and contacting the outwardly flared portion of the inner tubewithin the recess, thereby sealingly supporting the inner tube withinthe outer tube.
 27. The method of claim 26, wherein inserting the innertube within the open top of the outer tube to a position in which theoutwardly flared portion of the inner tube extends below a top edge ofthe recess of the inner surface of the outer tube causes air trappedbetween the inner tube and the outer tube to pass through the recess andvent to atmospheric pressure.
 28. The method of claim 26, wherein thecontacting step further comprises contacting the outwardly flaredportion of the inner tube with the top edge of the recess.
 29. Themethod of claim 26, wherein the recess of the outer tube extendscircumferentially around the inner surface of the outer tube.
 30. Themethod of claim 26, wherein the recess of the outer tube extendslongitudinally to the open end of the outer tube.
 31. The method ofclaim 26, wherein at least a portion of the inner tube has an externaldiameter which is smaller than an internal diameter of at least aportion of the outer tube to form an annular gap therebetween.
 32. Themethod of claim 31, wherein the inserting step further comprisesdeforming the outwardly flared portion of the inner tube below the topedge of the recess of the inner surface of the outer tube to cause airtrapped between the inner tube and the outer tube to pass through therecess and vent to atmospheric pressure.
 33. The method of claim 32,wherein the inner surface of the outer tube further comprises aprotrusion adjacent the recess for causing the outwardly flared portionto deform when the outwardly flared portion of the inner tube extendsbelow the top edge of the recess of the inner surface of the outer tube.34. The method of claim 32, wherein inserting the outwardly flaredportion of the inner tube below the top edge of the recess of the innersurface of the outer tube causes the inner tube to be biased toward theopen end of the outer tube.
 35. The method of claim 34, wherein theouter surface of the closed bottom of the inner tube is in contact withthe inner surface of the closed bottom of the outer tube when theoutwardly flared portion of the inner tube extends below the top edge ofthe recess of the inner surface of the outer tube, thereby causing theinner tube to be biased toward the open end of the outer tube.
 36. Themethod of claim 26, wherein the outer tube further comprises alongitudinal groove extending between the recess on the inner surface ofthe outer tube to the open end of the outer tube.
 37. A containerassembly comprising: an outer tube having a closed bottom, an open topand a side wall extending therebetween, said side wall defining an innersurface and an outer surface, said inner surface having a recessadjacent the open top thereof; an inner tube disposed within the outertube, said inner tube having a closed bottom, an open top and a sidewall having an inner surface and an outer surface extendingtherebetween, the side wall of the inner tube being shorter than theside wall of the outer tube and including an outwardly flared portionadjacent the open top of the inner tube and extending within the recessof the outer tube, a portion of the outwardly flared portion of theinner tube being baised within the recess of the outer tube to sealinglysupport the inner tube within the outer tube.
 38. The container assemblyof claim 37, wherein a top portion of the outwardly flared portion ofthe inner tube is baised against a top edge of the recess of the outertube to sealingly support the inner tube within the outer tube.
 39. Thecontainer assembly of claim 37, wherein at least a portion of said innertube has an external diameter which is smaller than an internal diameterof the outer tube to form an annular gap therebetween, the annular gapextends in equilibrium with atmospheric pressure at the time ofassembly.
 40. The container assembly of claim 39, wherein the annulargap is vented to atmospheric pressure during assembly through aninterference engagement between the inner tube and the outer tube at therecessed area of the outer tube.
 41. The method of claim 37, wherein therecess of the outer tube extends circumferentially around the innersurface of the outer tube.
 42. The method of claim 37, wherein therecess of the outer tube extends longitudinally to the open end of theouter tube.
 43. The method of claim 37, further comprising alongitudinal groove extending between the recess on the inner surface ofthe outer tube to the open end of the outer tube.
 44. The containerassembly of claim 37, wherein the outer surface of the closed bottom ofthe inner tube is in contact with the inner surface of the closed bottomof the outer tube.
 45. The container assembly of claim 37, wherein theouter container is formed from a polymeric material.
 46. The containerassembly of claim 37, wherein the outer container comprises polyethyleneterephthalate.
 47. The container assembly of claim 37, wherein the innercontainer is formed from a polymeric material.
 48. The containerassembly of claim 37, wherein the inner container comprisespolypropylene.